Plates containing a multiplicity of wells for holding samples of chemicals, cells or other biological materials for observation, are known in the art. Commonly, such plates have a 3:2 aspect ratio and thus contain 24 (4×6), 96 (8×12), 384 (16×24), or 1536 (32×48) wells; a typical 96-well plate is 128 mm long and 86 mm wide, and standards for the footprint and bottom outside flange of 96-well plates are described in ANSI/SBS 1-2004 and ANSI/SBS 3-2004, respectively.
Such multi-well plates, also sometimes referred to as microwell plates or microtiter plates depending on the volume of the wells, are generally constructed of plastic, e.g. polystyrene, polypropylene or polycarbonate, or a combination of such materials, in some cases also incorporating glass in the bottom portion of the plate. In many applications, the bottom of the well is transparent to a frequency of light that will be used to observe the sample. The size of wells in terms of depth, height, and total volume, as well the shape of the wells and the shape of the bottoms of the wells, varies in accordance with the particular use to which the plate is to be put.
Examples of commercial suppliers of such plates are:
Perkin-Elmer (see http://www.perkinelmer.com/CMSResources/Images/44-73879SPC_MicroplateDimensionsSummaryChart.pdf);
Sigma-Aldrich (see http://www.sigmaaldrich.com/labware/labware-products.html?TablePage=9576216); and
Thermo-Scientific (see http://www.thermoscientific.com/ecomm/servlet/productscatalog_11152_81996_-1_4).
One area in which widespread use of such plates is made is high-throughput screening for the testing of compounds in drug development, binding assays for antigens and the like.
Often, in high-throughput screening and other applications, automated machinery is used to dispense a volume of liquid into some or all of the wells simultaneously, for example, by dispensing fluid simultaneously into the wells of an 8-well row in a 96-well plate or into all the wells of a 384-well plate. However, if the amount of liquid added to a specific well is incorrect, such fact may not become known until the entire experiment is completed; and if the specific well to which the incorrect amount of fluid was added is not identified, it may be necessary to disregard the results for the entire plate.